1. Field of the Disclosure
This disclosure generally relates to an input device and, more particularly, to an optical navigation device and a power saving method thereof.
2. Description of the Related Art
A user can interact with a display device through various input devices such as a touch panel, a pointing device, an optical mouse, a keyboard and etc. In order to increase the operational convenience, some peripheral devices can communication with the display device using the wireless technologies but the peripheral devices using wireless communication technologies do not have a power line directly connected to a power supply such that various power saving mechanisms are provided for extending the lifetime of battery.
For example in an optical mouse, when the optical mouse is not operated by a user for a predetermined time interval, a sleep mode is entered. In the sleep mode, for example it is able to use a slow clock signal so as to decrease the total power consumption. For example referring to FIG. 1, it shows two clock signals used in the conventional optical mouse, e.g. including a main clock (main CLK) and a sleep clock (sleep CLK), and the two clock signals are generated simultaneously. In the normal operation mode the optical mouse operates at the main clock and in the sleep mode the optical mouse operates at the sleep clock. However, this power saving mechanism can save power only in the sleep mode but can not save power in the normal operation mode.
Accordingly, the present disclosure further provides a navigation device and a power saving method thereof that may save power in both the normal operation mode and the sleep mode so as to effectively reduce the total power consumption of the device.